Friday, November 09, 2018

Comparing Understanding of Graphs Between Physics and Psychology Students

I ran across this paper a while back, but didn't get to reading it carefully till now.

If you have followed this blog for any considerable period of time, you would have seen several posts where I emphasized the importance of physics education, NOT just for the physics knowledge, but also for the intangible skills that comes along with it. Skills such as analytical ability and deciding on the validity of what causes what are all skills that transcends the subject of physics. These are skills that are important no matter what the students end up doing in life.

While I had mentioned such things to my students during our first day of class each semester, it is always nice when there are EVIDENCE (remember that?) to back such claim. In this particular study, the researchers compare how students handle and understand the information that they can acquire from graphs on topics outside of their area of study.

The students involved are physics and psychology students in Zagreb, Croatia. They were tested on their understanding of the concept of slope and area under the graph, their qualitative and quantitative understanding of graphs, and comparing their understanding of graphs in the context of physics and finance. For the latter area (finance), both groups of students did not receive kind of lessons in that subject area and thus, are presumably unfamiliar with both groups.

Before we proceed, I found that in Croatia, physics is a compulsory subject in pre-college education there, which is quite heartening.

Physics is taught as a compulsory subject in the last two grades of all elementary schools and throughout four years of most of high schools in Croatia. Pupils are taught kinematics graphs at the age 15 and 16 (last grade of elementary school and first year of high school). Psychology students were not exposed to the teaching on kinematics graphs after high school, while physics students learned about kinematics graphs also in several university courses. Physics and psychology students had not encountered graphs related to prices, money, etc., in their formal education.

So the psychology students in college are already familiar with basic kinematics and graphs, but did not go further into it once they are in college, unlike physics students. I'd say that this is more than what most high school students in the US have gone through, since Physics is typically not required in high schools here.

In any case, the first part of the study wasn't too surprising, that physics students did better overall at physics questions related to the slope and area under the graph. But it was interesting that the understanding of what "area under the graph" tends to be problematic for both groups. And when we got to the graphs related to finance, it seems clear that physics students were able to extract the necessary information better than psychology students. This is especially true when it comes to the quantitative aspect of it.

You should read the in-depth analysis and discussion of the result. I'll quote part of their conclusion here:

All students solved the questions about graph slope better than the questions about the area under a graph. Psychology students had rather low scores on the questions about area under a graph, and physics students spent more time than psychology students on questions about area under a graph. These results indicate that area under a graph is quite a difficult concept that is unlikely to be developed without formal teaching and learning, and that more attention should be given to this topic in physics courses.

Physics and psychology students had comparable scores on the qualitative questions on slope which indicates that the idea of slope is rather intuitive. However, many psychology students were not able to calculate the slope, thus indicating that their idea of slope was rather vague. This suggests that the intuitive idea of slope, probably held by most students, should be further developed in physics courses and strongly linked to the mathematical concept of slope that enables students to quantify slope.

Generally, physics students solved the qualitative and the quantitative questions equally well, whereas psychology students solved qualitative questions much better than the quantitative questions. This is further evidence that learning physics helps students to develop deeper understanding of concepts and the ability to quantitatively express relationships between quantities.

The key point here is the "transfer" of knowledge that they have into an area that they are not familiar with. It is clear that physics students were able to extract the information in the area of finance better than psychology students. This is an important point that should be highlighted, because it shows how skills learned from a physics course can transfer to other areas, and that a student need not be a physics major to gain something important and relevant from a physics class.